This paper introduces TLAD(temporal logic based animation description)model and an animation description language SDL/A based on this model. SDL/A haspowerful description functions, and is convenient to express hierarchy abstract specification and the step -wise refinement procedure of designing an animation. This language can be used to describe multiactor action concurrency. It is easy to be integrated into a powerful CASE environment-XYZ system. This paper mainly introduces the design philosophy and the implementation techniques of SDL/A.